cyberstrikeus 2.18 Disable Mounting of cramfs Filesystems (Not Scored)
Profile Applicability
- Level 2
Description
The cramfs filesystem type is a compressed read-only Linux filesystem embedded in small footprint systems. A cramfs image can be used without having to first decompress the image.
Rationale
Removing support for unneeded filesystem types reduces the local attack surface of the server. If this filesystem type is not needed, disable it.
Audit Procedure
Using Command Line
/sbin/modprobe -n -v cramfs
/sbin/lsmod | grep cramfs
Expected Result
The first command should output install /bin/true. The second command should produce no output (module not loaded).
Remediation
Using Command Line
Edit or create the file /etc/modprobe.d/CIS.conf and add the following line:
install cramfs /bin/true
Default Value
By default, the cramfs module is available for loading.
References
- CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0
Profile
Level 2 - Not Scored